1. Field of the Invention
The present invention relates to an electronic data collection system for managing and controlling information in a restaurant. More particularly, the present invention relates to an improvement in such system which has a radio communication mode and another communication mode by electromagnetic induction, and has a function of changing from one communication mode to the other.
2. Description of the Prior Art
Various types of interactive systems are known employing portable data entry devices which communicate with information processing apparatus. Gary O. Sandstedt, U.S. Pat. Nos. 4,415,065 and 4,569,421 disclose a vending system particularly adapted for a restaurant which includes hand held portable data entry devices and an information processing apparatus. The hand held portable data entry devices also include wireless transceiver apparatus for bi-directional communications with the information processing apparatus. However, radio waves used in such a data collection system having a wireless communication function are generally liable to be influenced by various noises external the system. The drawback of this system is that an information transfer becomes impossible when errors occur under the influence of various noises during the transfer of information between the hand held portable data entry devices and the information processing apparatus.